Yes it is likely that you will be using LaTeX for submitting your paper but first you will need to find an appropriate journal for it and follow THEIR style guidelines. It's not as simple as "hey I wrote this, wanna publish it?" but a rather long and complex process where you draft it based on the journal's requirements (word-counts, formatting, citations, ...).
As for, why not publish to Science? Because he won't get in and it's a huge waste of time to prepare a manuscript for them. For someone writing their first journal article, you will need some practice in academic writing, even if your research is good - that doesn't cut it for journals like Science - your research has to be groundbreaking. My recommendation is to find a cool conference that fits your topic well and submit it there. Much more rewarding as you also get to present your paper and have an actual audience. Good luck, it's a lengthy process to publish but if you have any results you will find the appropriate venue!